V1.02
Thom Hogan’s Complete Guide to the Nikon D300
Page 617
length. Note that you can’t have much subject motion if
the background exposure is close to the subject exposure.
• Why do I have to use Standard TTL?
Because Nikon’s
Balanced Fill-Flash mode uses internal variants of both
Flash Exposure Compensation
and
Exposure
Compensation to “balance” the ambient (background) and
subject lighting in bright light. These compensations are
unknown and vary based upon scene contrast, scene
brightness, focus distance, and more. In dark light, the
camera alters its strategy a bit and treats the flash as the
primary source of light for your subject, though it still may
apply slight exposure compensations based upon what the
meter sees. Thus,
TTL BL
produces results that are not
always repeatable. You may take pictures in one set of
lighting that are good, in another, bad. Slight changes in
camera position sometimes produce slight differences in
exposure when you don’t expect them to. That’s why I tell
you to take control of what the flash is doing and dial in
your own compensation.
Third Party Flash Units
The i-TTL flash units required by the D300 to perform TTL
mean you are restricted to the SB-400, SB-600, SB-800, and
SB-R200 if you want to purchase an external flash and retain
the most available capabilities.
It took over two years after D-TTL came out for any third party
flashes to support it and those implementations were so-so. So
it may be awhile before we see any highly desirable i-TTL
units from other companies. Metz makes a flash that can
operate with i-TTL (though its secondary flash head—the
reason why many gravitate to Metz—is incompatible).
Sigma’s latest flashes are also i-TTL compatible, though I’ve
had inconsistent results with them. Worse still, Nikon keeps
tuning TTL BL with each new camera—including the D300—
and that makes me a bit leery of the companies that are
reverse engineering to maintain compatibility.
